1. Field of the Invention
The invention relates to a safety hook, more particularly to a safety hook with a safety lock unit.
2. Description of the Related Art
FIG. 1 illustrates a conventional safety hook 9 that includes an inverted J-shaped hook body 91 that defines a hook mouth, a latch unit 92 pivoted to the hook body 91 about a first axis (L1) below the hook mouth for blocking and unblocking the hook mouth, a safety lock unit 93 pivoted to the hook body 91 about a second axis (L2) above the first axis (L1) for preventing undesired unblocking movement of the latch unit 92, and a releasing unit 94 that is pivoted to the hook body 91 about a third axis (L3) slightly above the second axis (L2) and that is pivotably connected to the safety lock unit 93. The releasing unit 94 has a spring-biased operating end portion 941 for releasing the latch unit 92 from a locked state.
When the latch unit 92 is to be unlocked, the operating end portion 941 of the releasing unit 94 is pushed to rotate the releasing unit 94 about the third pivot axis (L3), which results in rotation of the safety lock unit 93 about the second pivot axis (L2) in the same direction to a releasing position that permits unlocking of the latch unit 92. The latch unit 92 is formed with an operating protrusion 922 that is disposed opposite to the operating end portion 941 in order to permit the user to simultaneously press the operating end portion 941 of the releasing unit 94 and to move the latch unit 92 using one hand.
The conventional safety hook 9 is disadvantageous in that the releasing unit 94 has a relatively complicated structure. In addition, since the force applied to the operating protrusion 922 of the latch unit 92 is substantially perpendicular to the force applied to the operating end portion 941 of the releasing unit 94, unlocking operation of the latch unit 92 is relatively inconvenient.